[BEAM-8780]Improve docker container release script

[Hannah-Jiang]

Improve docker container script: reuse verified rc images instead of recreating images.

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Post-Commit Tests Status (on master branch)

Lang	SDK	Apex	Dataflow	Flink	Gearpump	Samza	Spark
Go		---	---		---	---
Java
Python		---			---	---
XLang	---	---	---		---	---	---

Pre-Commit Tests Status (on master branch)

---	Java	Python	Go	Website
Non-portable
Portable	---		---	---

See .test-infra/jenkins/README for trigger phrase, status and link of all Jenkins jobs.

[Hannah-Jiang]

R: @markflyhigh
Cc: @kyle-winkelman do we need to do the same thing for Flink images?
Cc: @Ardagan

[Ardagan]

LGTM overall.
There's also a way to do this without pulling image. See https://issues.apache.org/jira/browse/BEAM-8780
Would be great if we can utilize that one.

[Hannah-Jiang]

LGTM overall.
There's also a way to do this without pulling image. See https://issues.apache.org/jira/browse/BEAM-8780
Would be great if we can utilize that one.

Thanks for reviewing it.
I investigate both options mentioned at BEAM-8780. The option with updating manifest is not recommended to use in production. (https://docs.docker.com/engine/reference/commandline/manifest/). The second option with docker build creates new images, so that is not an option here.

After all, I think pull, tag and push process is the most stable and easy to understand for now.

[Hannah-Jiang]

The PR is ready to be merged to master.